An efficient configuration for simultaneous electromembrane extraction of acidic and basic drugs on a chip

In the present study, a new chip was designed for simultaneous electromembrane extraction (EME) of acidic and basic analytes. The method followed by the HPLC-UV analysis, was used for simultaneous extraction and determination of trace amounts of target analytes with different properties. Ibuprofen (IBU), as an acidic model analyte, and disopyramide (DIS) and lidocaine (LID), as basic model analytes, were selected. The chip was composed of three polymethylmethacrylate (PMMA) plates. The chamber for the sample solution was set in the middle plate. Two other chambers were carved on the other plates and they were acted as two acceptor phases’ reservoirs. Two stainless steel electrodes, which were responsible for applying a DC electrical potential on both sides of the supported liquid membranes (SLMs), were placed in the bottom of acceptor phases chambers and connected to a power supply. The two porous polypropylene membrane sheets, which were impregnated with different organic solvents, were used to separate the plates. Effective parameters such as SLM composition (1-octanol for acidic analyte and NPOE+5%DEHP for basic analytes), pH of donor phase and acceptor phases, applied voltage across SLM, and extraction time were optimized. Under the optimized conditions, the calibration curves were linear with coefficient of determinations (R2) higher than 0.991 in the water, urine, and blood plasma samples. The obtained LODs were less than 5.0 µg L−1 and 1 µg L−1 for the basic and acidic analytes, respectively. The results demonstrated that on-chip EME would be used most effectively for extraction and determination of IBU, DIS, and LID in biofluids.